CreatePermissionlevel.ps1

  
#Credentials to connect to office 365 site collection url 
$url ="https://velegandla.sharepoint.com"
$username="[email protected]"
$password="yourpassword"
$Password = $password |ConvertTo-SecureString -AsPlainText -force

Write-Host "Load CSOM libraries" -foregroundcolor black -backgroundcolor yellow
Set-Location $PSScriptRoot
Add-Type -Path (Resolve-Path "Microsoft.SharePoint.Client.dll")
Add-Type -Path (Resolve-Path "Microsoft.SharePoint.Client.Runtime.dll")


Write-Host "CSOM libraries loaded successfully" -foregroundcolor black -backgroundcolor Green 

Write-Host "authenticate to SharePoint Online site collection $url and get ClientContext object" -foregroundcolor black -backgroundcolor yellow  
$Context = New-Object Microsoft.SharePoint.Client.ClientContext($url) 
$credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($username, $password) 
$Context.Credentials = $credentials 
$context.RequestTimeOut = 5000 * 60 * 10;
$web = $context.Web
$site = $context.Site 
$context.Load($web)
$context.Load($site)
try
{
  $context.ExecuteQuery()
  Write-Host "authenticateed to SharePoint Online site collection $url and get ClientContext object succeefully" -foregroundcolor black -backgroundcolor Green
}
catch
{
  Write-Host "Not able to authenticateed to SharePoint Online site collection $url  $_.Exception.Message" -foregroundcolor black -backgroundcolor Red
  return
}

#Define Custom permission level
$permissionlevel = "addListItems, editListItems, viewListItems"

#function create Custom Role Definitions
 function CreateRoleDefinitions($permName, $permDescription, $permissionString)
 {
    $roleDefinitionCol = $web.RoleDefinitions
    $Context.Load($roleDefinitionCol)
    $Context.ExecuteQuery()
    $permExists = $false

    #Check if the permission level is exists or not
    foreach($role in $roleDefinitionCol)
    {
       if($role.Name -eq $permName)
        {
            $permExists = $True
        }
    }
        
    Write-Host Creating Pemission level with the name $permName  -foregroundcolor black -backgroundcolor Yellow
    if($permExists -ne $True)
    {
        try
        {
            $spRoleDef = New-Object Microsoft.SharePoint.Client.RoleDefinitionCreationInformation
            $spBasePerm = New-Object Microsoft.SharePoint.Client.BasePermissions
                
            $permissions = $permissionString.split(",");
            foreach($perm in $permissions)
            {
                $spBasePerm.Set($perm) 
            }

            $spRoleDef.Name = $permName
            $spRoleDef.Description = $permDescription
            $spRoleDef.BasePermissions = $spBasePerm    

            $roleDefinition = $web.RoleDefinitions.Add($spRoleDef)

            $Context.ExecuteQuery()

            Write-Host Pemission level with the name $permName created -foregroundcolor black -backgroundcolor Green
        }
        catch
        {
            Write-Host There was an error creating Permission Level $permName : Error details $_.Exception.Message -foregroundcolor black -backgroundcolor Red
        }
    }
    else
    {
        Write-Host Pemission level with the name $permName already exists -foregroundcolor black -backgroundcolor Red
    }
 }
 
 #calling role definition function
 CreateRoleDefinitions -permName "SPJ Custom Permissions" -permDescription "This permission level is created for training site and contains add/edit/View item permissions" -permissionString $permissionlevel